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Synthesis and structure of Cu_5(BTA)_6(TTA)_4·5DMF, a copper-nitrogen cluster containing η~3-benzotriazolate

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Chinese Science Bulletin 2002年第11期47卷 890-893页

作者： WANG Jinling, YU Ming, YANG Yun, ZHANG Shuming & MIAO FangmingTianjin normal university, Tianjin 300074, china Tianjin Light Industry College, Tianjin 300222, china Tianjin normal university Tianjin China Tianjin Light Industry College Tianjin China

The title cluster compound-Cu5(BTA)6(TT-A)4·5DMF was prepared using thenyltrifluoroacetone and benzotriazolate ligands. The crystal structure indicates that a tetrahedral array of Cu(l), Cu(2), Cu(3) and Cu(4) ions surrounding a central Cu(5) ion are held together by bridging tridentate BTA- and terminated by TTA- bond cap. The three nitrogen atoms of a BTA- bond three different copper ions to form a η3-benzotriazolate. The central Cu ion has a distorted octahedral structure and the surrounding Cu ions are 5 coordinated forming distorted tetragonal structures. The distances between the surrounding Cu(Ⅱ) ions and the central Cu(Ⅱ) ion are in the range of 0.3561-0.3755 nm and those between the surrounding Cu(Ⅱ) ions are in the range of 0.5785-0.6301nm.

关键词： benzotriazolate (BTA) thenyltrifluoroacetone (TTA) copper-nitrogen cluster synthesis crystal structure.

Preparation of nanoparticles with an environment-friendly approach

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Journal of Environmental Sciences 2009年第6期21卷 727-730页

作者： YAO Kefu,PENG Zhen,FAN Xiaolin Key Laboratory of Advanced Materials Processing Technology,Ministry of Education of china,department of Mechanical Engineering,Tsinghua university,Beijing 100084,china. Key Laboratory of Advanced Materials Processing Technology Ministry of Education of China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Developing various approaches for preparing high performance materials has long been topics and tasks both for scientists and for engineers. Despite that many methods have been developed for preparing nanomaterials, developing simple and environment-friendly ways for preparing nanomaterials is very attractive. Here a simple approach of synthesizing Fe3O4 nanoparticles by arc-discharge submerging in water was reported. The results showed that by this method Fe3O4 nanoparticles can be synthesized at large scale. The as-prepared Fe3O4 nanoparticles exhibited uniform spherical shape and their diameters varied with arc-discharging parameters. The experimental results showed that the size of the synthesized Fe3O4 nanoparticles can be controlled through adjusting the processing parameters. Since no vacuum system has been used, the synthesizing process is greatly simplified. In addition, only cheap deionized water and industrial iron bar are used and no pollution or harmful byproducts are found in the synthesis process. It indicated that the present approach is a simple, low-cost and environment-friendly one for preparing nanoparticles.

关键词： nanoparticles preparation approach Fe3O4

Evidence for metasomatic mantle carbonatitic magma extrusion in Mesoproterozoic ore-hosting dolomite rocks in the middle Kunyang rift, central Yunnan, china

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Progress in Natural Science:Materials International 2008年第8期18卷 965-974页

作者： Yongbei Zhanga,b,c, Hua Bia,*, Longshi Yua, Shihua Sunc, Jiaxiang Qiub, Chengyan Xub, Hao Wang b, Renjing Wang b a The department of Resources, Environment and Tourism, Hainan normal university, No. 432, Yinpo Road, Longshepo, Haikou 57000, china b Key Laboratory of Mineral Resources, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china c Faculty of Earth Sciences, china university of Geosciences, Wuhan 470074, china The department of Resources Environment and Tourism Hainan Normal University No. 432 Yinpo Road Longshepo Haikou 57000 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Faculty of Earth Sciences China University of Geosciences Wuhan 470074 China

The Kunyang rift lying on the western margin of the Yangtze platform is a rare Precambrian Fe-Cu mineralization zone. WudingLufeng basin that is an important part of the zone is located on the west edge in the middle of the rift. The most important ore-hosting rocks are Mesoproterozoic dolomite rocks in the basin controlled by a ring fracture system, which is a fundamental structure of the basin. Plenty of silicate minerals and acicular apatite, feldspar phenocrysts and small vesicular, flown line and flown plane structures, melt inclusion and high temperature fluid inclusion found in most ore-hosting dolomites suggest that this kind of rocks could not be sedimentary dolomite, marble or hydrothermal carbonate rocks. The Zr/Hf and Nb/Ta values of the rocks are identical with those of associated mantle-derived rocks, and vary widely. For the monomineral dolomite, d18OSMOW‰ = +5.99 to +18.4 and d13CPDB‰ = à3.01 to +0.94, which fall within the range for all carbonatitic volcanic rocks of the world. As for the accessory minerals, the values of d18OSMOW‰ of magnetite (=+3.47 to +5.99‰) are close to that of the mantle (4S‰ values of sul?des (à5.09 to +5.78, averaging +1.50) are close to that of meteorite. For all the ore-bearing dolomite rocks, eNd = +0.19 to +2.27, and the calculated ISr = 0.699143, while for the associated mantle-derived rocks, eNd = +3.18 to +3.72. All the data suggest that the mineral assemblage is not only igneous but also of metasomatic mantle origin. And the presence of acicular apatite indicates that the rocks were formed by magma rapidly cooling. And the phenocryst texture and vesicular, flown and ropy and pyroclastic structures suggest that the igneous rocks were extrusive. Therefore, the ore-bearing dolomite rocks are carbonatitic volcanic rocks. This conclusion implies that most iron and copper ore deposits hosted in the dolomite rocks should be of the carbonatite type.

关键词： Central Yunnan Kunyang rift Precambrian Mineralization Carbonatitite Volcanic rocks Petrogenesis Iron and copper ore deposit

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学校发展规划制订与实施的困境

教育发展研究 2010年第2期30卷 51-55页

作者：贺菲肖全胜南京师范大学课程与教学研究所博士后南京210097 南京市栖霞区实验小学校长南京210046

要实现"学校发展规划"对学校自主发展的引导价值,必须确保所制订的发展规划本身具有合理性,同时要使校长和教师能够充分理解发展规划的意义并将其有效实施。当前,学校在制订发展规划过程中存在着:对优质教育理解的偏颇、办学理念的空洞... 详细信息

要实现"学校发展规划"对学校自主发展的引导价值,必须确保所制订的发展规划本身具有合理性,同时要使校长和教师能够充分理解发展规划的意义并将其有效实施。当前,学校在制订发展规划过程中存在着:对优质教育理解的偏颇、办学理念的空洞、特色发展的错误定位、发展领域的的确定缺乏重点等问题;在实施发展规划过程中面临着"理性"规划与"非理性"实践、学校教育价值取向与教育外在要求、学校自主发展与传统管理模式等的冲突。实践中,要使制订学校发展规划的成为学校的自主愿选择,并以坚定的信念与持续行动来实施规划。

关键词：学校发展规划规划文本规划价值

The Evaluation of Connection Coefficients on an Interval

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 252-255页

作者： Xiaolin ZHOU and Wu ZHANG(department of Applied Mathematics, Xi’an Jiao Tong university, Xi’an 710049, china) department of Applied Mathematics Xi'an Jiaotong University Xi'an 710049 China

A connection coefficient is an interval of products of wavelet basis functions,their derivatives and their translates. It can be used to solve PDEs numerically by the wavelet- Galerkin method. This paper presents an e... 详细信息

关键词： connection coefficients wavelets

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基于正交小波包变换的判决反馈盲均衡算法

系统仿真学报 2010年第3期22卷 570-572页

作者：郭业才杨超南京信息工程大学电子与信息工程学院南京210044 安徽理工大学电气与信息工程学院淮南232001

针对严重线性失真的水声信道,在分析正交小波包变换理论和判决反馈盲均衡算法的基础上,利用正交小波包变换良好的去相关性特性,对判决反馈盲均衡算法的前馈滤波器权向量进行修正,提出了基于正交小波包变换的判决反馈盲均衡算法(WPT-DFE... 详细信息

针对严重线性失真的水声信道,在分析正交小波包变换理论和判决反馈盲均衡算法的基础上,利用正交小波包变换良好的去相关性特性,对判决反馈盲均衡算法的前馈滤波器权向量进行修正,提出了基于正交小波包变换的判决反馈盲均衡算法(WPT-DFE)。与基于正交小波变换的判决反馈盲均衡算法(WT-DFE)和常规判决反馈盲均衡算法(CMA-DFE)相比,该算法具有收敛速度快、跟踪性能好、稳态误差小的特点。水声信道的仿真结果,验证了算法的有效性。

关键词：正交小波包变换判决反馈盲均衡水声信道

Strong convergence rate of a kind of Pickandstype estimator

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西南师范大学学报（自然科学版） 1996年第5期21卷 430-433页

作者： Peng Zuoxiang (department of Mathematics, Southwest china normal university, Chongqing 630715)

ＳｔｒｏｎｇｃｏｎｖｅｒｇｅｎｃｅｒａｔｅｏｆａｋｉｎｄｏｆＰｉｃｋａｎｄｓｔｙｐｅｅｓｔｉｍａｔｏｒ￥ＰｅｎｇＺｕｏｘｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＳｏｕｔｈｗｅｓｔＣｈｉｎａＮｏｒｍａ... 详细信息

ＳｔｒｏｎｇｃｏｎｖｅｒｇｅｎｃｅｒａｔｅｏｆａｋｉｎｄｏｆＰｉｃｋａｎｄｓｔｙｐｅｅｓｔｉｍａｔｏｒ￥ＰｅｎｇＺｕｏｘｉａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＳｏｕｔｈｗｅｓｔＣｈｉｎａＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ，Ｃｈｏｎｇ...

关键词： Pickands型估计量强收敛速度

NONMRAMETRIC AND SEMIPARAMETRICREGRESSION MODELS WITH LOCALLYGENERALIZED GAUSSIAN ERROR

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Systems Science and Mathematical Sciences 1997年第1期10卷 80-90页

作者： HU Shuhe (department Of Mathematics, Anhui university, Hefei 230039, china)

Under a locally generalized Gaussian error’s structure, we obtain strong uniform consistency for nonparametric regression function estimators and strong consistency for parametric component estimators in semiparametr... 详细信息

关键词： Nonparametric semiparametric regression strong consistency

A NEW CHARACTERIZATION OF NBU CLASS OF LIFE DISTRIBUTIONS WITH APPLICATION

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Journal of Systems Science & Complexity 2003年第2期16卷 222-228页

作者： LI Xiaohu (department of Mathematics, Lanzhou university, Lanzhou 730000, china) department of Mathematics Lanzhou University Lanzhou 730000

Assume an unreliable workstation performing jobs with a random service time, namely, it occasionally breaks down because of unexpected interruptions. As an interruption really occurs, the station is instantaneously repaired and the uncompleted job is restarted again from the beginning till a job is completed without being interrupted. The total service time is shown to be NBU if and only if the total time it takes to finish each job with interruptions is stochastically larger than that without them, irrespective of when and how the breakdowns occur. As an application, a nonparametric procedure is developed to test for the strict NBU property of the service time. Finally, some numerical simulations are presented as well.

关键词： NBU interruptions stochastically larger L-statistic